Spatial features of non-thermal SZ effect in galaxy clusters

We investigate the spatial behaviour of the total comptonization parameter $y_{tot}$ evaluated for a galaxy cluster containing two population of electrons: the thermal population, with energy around some KeV and whose trace is evident in the X-ray emission of the ICM (Intra-Cluster Medium), and the relativistic population, which give rise to the radio halo emission found in several clusters of galaxies. We present the first results obtained from our analysis showing that there are remarkable features in such spatial trend, which might throw a new light in understanding the cluster internal processes.Comment: 4 pages, 1 figure, to appear in the proceedings of the 2k1bc workshop ""Experimental comsology @ millimetre wavelengths", july 9-12 2001, Breuil-Cervinia, Ital

CO2-crystal wettability in potassic magmas. Implications for eruptive dynamics in light of experimental evidence for heterogeneous nucleation.

The volatile content in magmas is fundamental for the triggering and style of volcanic eruptions. Carbon dioxide, the second most abundant volatile component in magmas after H2O, is the first to reach saturation upon ascent and depressurization. We investigate experimentally CO2-bubble nucleation in trachybasalt and trachyte melts at high temperature and high pressure (HT and HP) through wetting-angle measurements on different (sialic, mafic or oxide) phenocryst phases. The presence of crystals lowers the supersaturation required for CO2- bubble nucleation up to 37 per cent (heterogeneous nucleation, HeN), with a minor role of mineral chemistry. Different from H2O-rich systems, feldspar crystals are effective in reducing required supersaturation for bubble nucleation. Our data suggest that leucite, the dominant liquidus phase in ultrapotassic systems at shallow depth (i.e. <100 MPa), facilitates late-stage, extensive magma vesiculation through CO2 HeN, which may explain the shifting of CO2-rich eruptive systems towards an apparently anomalous explosive behaviour

Older migrants reflecting on aging through attachment to and identification with places

With increasing numbers of older migrants adopting a transnational lifestyle or returning to their country of origin following retirement, the sense of attachment to and identification with the places they inhabit remains an under explored field of enquiry. Through an ethnographic approach, this paper seeks to raise awareness of the diversity within a group of older migrants, given the heterogeneity of affective bonds established with places. By highlighting the perspective of older Italian migrants living in Newcastle upon Tyne, UK, this paper illustrates the role of a sense of identification with the context of migration in later life. In referring to migration as a process of transformation, some older Italians re-define their identities, as these become interwoven with the characteristics of the places in which they grow older. However, older migrants' sense of attachment to places also reveals the complexity of aging in the context of migration, when a sense of identification with these is never fully achieved in older age. This paper argues that the notion of aging that these older Italian migrants uphold is not only altered by their experience of migration, but also shaped through their identification with the places they inhabit, given formal and informal practices of identification. Thus, by addressing the determinants for a positive experience of aging in the context of migration, this paper challenges the ways in which older migrant groups are conceptualized in gerontological scholarship

Mars Regolith Simulant Ameliorated by Compost as In Situ Cultivation Substrate Improves Lettuce Growth and Nutritional Aspects

Heavy payloads in future shuttle journeys to Mars present limiting factors, making self-sustenance essential for future colonies. Therefore, in situ resources utilization (ISRU) is the path to successful and feasible space voyages. This research frames the concept of planting leafy vegetables on Mars regolith simulant, ameliorating this substrate’s fertility by the addition of organic residues produced in situ. For this purpose, two butterhead lettuce (Lactuca sativa L. var. capitata) cultivars (green and red Salanova®) were chosen to be cultivated in four dierent mixtures of MMS-1 Mojave Mars simulant:compost (0:100, 30:70, 70:30 and 100:0; v:v) in a phytotron open gas exchange growth chamber. The impact of compost rate on both crop performance and the nutritive value of green- and red-pigmented cultivars was assessed. The 30:70 mixture proved to be optimal in terms of crop performance, photosynthetic activity, intrinsic water use eciency and quality traits of lettuce. In particular, red Salanova® showed the best performance in terms of these quality traits, registering 32% more phenolic content in comparison to 100% simulant. Nonetheless, the 70:30 mixture represents a more realistic scenario when taking into consideration the sustainable use of compost as a limited resource in space farming, while still accepting a slight significant decline in yield and quality in comparison to the 30:70 mixture

Family functioning, identity commitments, and school value among ethnic minority and ethnic majority adolescents

Ethnic minority youth show worse school adjustment than their ethnic majority peers. Yet, it remains unclear whether this gap can be explained by differences in family functioning and consequent identity commitments. This study examined (1) whether family functioning relates to identity commitments over time and (2) whether identity commitments impact later school value (3) among minority and majority adolescents. Minority (N = 205, Mage = 16.25 years, 31.1% girls) and majority adolescents (N = 480, Mage = 15.73 years, 47.9% girls) participated in this preregistered three-wave longitudinal study (T1: March-April 2012; T2: October 2012; T3: March-April 2013). Dynamic Panel Models revealed that most within-person cross-lagged associations were not significant in the total sample. Yet, multigroup analyses revealed differences between groups: Stronger identity commitments related to lower school value among minority adolescents, but were unrelated to school value among majority adolescents over time. Additionally, higher school value increased identity commitments among minority youth, yet it decreased identity commitments among majority youth over time. The findings highlight the differential interplay between identity commitments and school adjustment for minority and majority adolescents, with important implications for their future life chances

Functionally graded plate fracture analysis using the field boundary element method

This paper describes the Field Boundary Element Method (FBEM) applied to the fracture analysis of a 2D rectangular plate made of Functionally Graded Material (FGM) to calculate Mode I Stress Intensity Factor (SIF). The case study of this Field Boundary Element Method is the transversely isotropic plane plate. Its material presents an exponential variation of the elasticity tensor depending on a scalar function of position, i.e., the elastic tensor results from multiplying a scalar function by a constant taken as a reference. Several examples using a parametric representation of the structural response show the suitability of the method that constitutes a Stress Intensity Factor evaluation of Functionally Graded Materials plane plates even in the case of more complex geometries

Triple Experiment Spectrum of the Sunyaev-Zeldovich Effect in the Coma Cluster: H_0

The Sunyaev-Zeldovich (SZ) effect was previously measured in the Coma cluster by the Owens Valley Radio Observatory and Millimeter and IR Testa Grigia Observatory experiments and recently also with the Wilkinson Microwave Anisotropy Probe satellite. We assess the consistency of these results and their implications on the feasibility of high-frequency SZ work with ground-based telescopes. The unique data set from the combined measurements at six frequency bands is jointly analyzed, resulting in a best-fit value for the Thomson optical depth at the cluster center, tau_{0}=(5.35 \pm 0.67) 10^{-3}. The combined X-ray and SZ determined properties of the gas are used to determine the Hubble constant. For isothermal gas with a \beta density profile we derive H_0 = 84 \pm 26 km/(s\cdot Mpc); the (1\sigma) error includes only observational SZ and X-ray uncertainties.Comment: 11 pages, 1 figur